Re: remaining sql/json patches

jian he <jian.universality@gmail.com>

From: jian he <jian.universality@gmail.com>
To: Amit Langote <amitlangote09@gmail.com>
Cc: Tomas Vondra <tomas.vondra@enterprisedb.com>, Himanshu Upadhyaya <upadhyaya.himanshu@gmail.com>, Alvaro Herrera <alvherre@alvh.no-ip.org>, Erik Rijkers <er@xs4all.nl>, Andres Freund <andres@anarazel.de>, Andrew Dunstan <andrew@dunslane.net>, PostgreSQL-development <pgsql-hackers@postgresql.org>
Date: 2024-03-20T06:51:48Z
Lists: pgsql-hackers

Commits

Same data as JSON: GET /api/v1/messages/:b64id/commits the thread's linked commits as JSON, with link sources. API reference →
  1. SQL/JSON: Various improvements to SQL/JSON query function docs

  2. SQL/JSON: Fix some obsolete comments.

  3. SQL/JSON: Fix issues with DEFAULT .. ON ERROR / EMPTY

  4. JSON_TABLE: Add support for NESTED paths and columns

  5. Fix JsonExpr deparsing to emit QUOTES and WRAPPER correctly

  6. Fix typo introduced in 6185c9737

  7. Add basic JSON_TABLE() functionality

  8. Avoid splitting errmsg string to span multiple lines

  9. Add SQL/JSON query functions

  10. Implement various jsonpath methods

  11. Add soft error handling to some expression nodes

  12. Adjust populate_record_field() to handle errors softly

  13. Refactor code used by jsonpath executor to fetch variables

  14. Test EXPLAIN (FORMAT JSON) ... XMLTABLE

  15. Simplify productions for FORMAT JSON [ ENCODING name ]

  16. Add trailing commas to enum definitions

  17. doc: add missing <returnvalue> and whitespace

  18. Add more SQL/JSON constructor functions

  19. Rename a nonterminal used in SQL/JSON grammar

  20. Some refactoring to export json(b) conversion functions

  21. Don't include CaseTestExpr in JsonValueExpr.formatted_expr

  22. Code review for commit b6e1157e7d

  23. Pass constructName to transformJsonValueExpr()

  24. Unify JSON categorize type API and export for external use

  25. Make some indentation in gram.y consistent

  26. Allow most keywords to be used as column labels without requiring AS.

  27. Reduce size of backend scanner's tables.

  28. Use perfect hashing, instead of binary search, for keyword lookup.

minor issues I found while looking through it.
other than these issues, looks good!

/*
 * Convert the a given JsonbValue to its C string representation
 *
 * Returns the string as a Datum setting *resnull if the JsonbValue is a
 * a jbvNull.
 */
static char *
ExecGetJsonValueItemString(JsonbValue *item, bool *resnull)
{
}
I think the comments are not right?

/*
 * Checks if the coercion evaluation led to an error.  If an error did occur,
 * this sets post_eval->error to trigger the ON ERROR handling steps.
 */
void
ExecEvalJsonCoercionFinish(ExprState *state, ExprEvalStep *op)
{
}
these comments on ExecEvalJsonCoercionFinish also need to be updated?


+ /*
+ * Coerce the result value by calling the input function coercion.
+ * *op->resvalue must point to C string in this case.
+ */
+ if (!*op->resnull && jsexpr->use_io_coercion)
+ {
+ FunctionCallInfo fcinfo;
+
+ fcinfo = jsestate->input_fcinfo;
+ Assert(fcinfo != NULL);
+ Assert(val_string != NULL);
+ fcinfo->args[0].value = PointerGetDatum(val_string);
+ fcinfo->args[0].isnull = *op->resnull;
+ /* second and third arguments are already set up */
+
+ fcinfo->isnull = false;
+ *op->resvalue = FunctionCallInvoke(fcinfo);
+ if (SOFT_ERROR_OCCURRED(&jsestate->escontext))
+ error = true;
+
+ jump_eval_coercion = -1;
+ }

+ /* second and third arguments are already set up */
change to
/* second and third arguments are already set up in ExecInitJsonExpr */
would be great.


commit message
<<<<
All of these functions only operate on jsonb values. The workaround
for now is to cast the argument to jsonb.
<<<<
should be removed?


+ case T_JsonFuncExpr:
+ {
+ JsonFuncExpr *jfe = (JsonFuncExpr *) node;
+
+ if (WALK(jfe->context_item))
+ return true;
+ if (WALK(jfe->pathspec))
+ return true;
+ if (WALK(jfe->passing))
+ return true;
+ if (jfe->output && WALK(jfe->output))
+ return true;
+ if (jfe->on_empty)
+ return true;
+ if (jfe->on_error)
+ return true;
+ }

+ if (jfe->output && WALK(jfe->output))
+ return true;
can be simplified:

+ if (WALK(jfe->output))
+ return true;